全文获取类型
收费全文 | 523篇 |
免费 | 42篇 |
国内免费 | 205篇 |
专业分类
安全科学 | 39篇 |
废物处理 | 31篇 |
环保管理 | 40篇 |
综合类 | 288篇 |
基础理论 | 98篇 |
污染及防治 | 198篇 |
评价与监测 | 26篇 |
社会与环境 | 21篇 |
灾害及防治 | 29篇 |
出版年
2023年 | 9篇 |
2022年 | 31篇 |
2021年 | 31篇 |
2020年 | 33篇 |
2019年 | 27篇 |
2018年 | 29篇 |
2017年 | 23篇 |
2016年 | 26篇 |
2015年 | 28篇 |
2014年 | 47篇 |
2013年 | 51篇 |
2012年 | 35篇 |
2011年 | 56篇 |
2010年 | 31篇 |
2009年 | 38篇 |
2008年 | 33篇 |
2007年 | 33篇 |
2006年 | 33篇 |
2005年 | 41篇 |
2004年 | 14篇 |
2003年 | 21篇 |
2002年 | 16篇 |
2001年 | 15篇 |
2000年 | 15篇 |
1999年 | 8篇 |
1998年 | 6篇 |
1997年 | 12篇 |
1996年 | 8篇 |
1995年 | 4篇 |
1994年 | 4篇 |
1993年 | 3篇 |
1992年 | 4篇 |
1991年 | 1篇 |
1990年 | 2篇 |
1989年 | 1篇 |
1988年 | 1篇 |
排序方式: 共有770条查询结果,搜索用时 15 毫秒
41.
Jianjun Niu Pat E. Rasmussen Amanda Wheeler Ron Williams Marc Chénier 《Atmospheric environment (Oxford, England : 1994)》2010,44(2):235-245
Factors and sources affecting measurement uncertainty associated with monitoring metals in airborne particulate matter (PM) were investigated as part of the Windsor, Ontario Exposure Assessment Study (WOEAS). The assessment was made using co-located duplicate samples and a comparison of two analytical approaches: ED-XRF and ICP-MS. Sampling variability was estimated using relative percent difference (RPD) of co-located duplicate samples. The comparison of ICP-MS and ED-XRF results yields very good correlations (R2 ≥ 0.7) for elements present at concentrations that pass both ICP-MS and ED-XRF detection limits (e.g. Fe, Mn, Zn, Pb and Cu). PM concentration ranges (median, sample number) of 24-h indoor PM10 and personal PM10 filters, and outdoor PM2.5 filters were determined to be 2.2–40.7 (11.0, n = 48) μg m?3, 8.0–48.3 (11.9, n = 48) μg m?3, and 17.1–42.3 (21.6, n = 18) μg m?3, respectively. The gravimetric analytical results reveal that the variations in PM mass measurements for same-day sampling are insignificant compared to temporal or spatial variations: 92%, 100% and 96% of indoor, outdoor and personal duplicate samples, respectively, pass the quality criteria (RPD ≤ 20%). Uncertainties associated with ED-XRF elemental measurements of S, Ca, Mn, Fe and Zn for 24-h filter samples are low: 78%–100% of the duplicate samples passed the quality criteria. In the case of 24-h filter samples using ICP-MS, more elements passed the quality criteria due to the lower detection limits. These were: Li, Na, K, Ca, Si, Al, V, Fe, Mn, Co, Cu, Mo, Ag, Zn, Pb, As, Mg, Sb, Sn, Sr, Th, Ti, Tl, and U. Low air concentrations of metals (near or below instrumental detection limits) and/or inadvertent introduction of metal contamination are the main causes for excluding elements based on the pass/fail criteria. Uncertainty associated with elemental measurements must be assessed on an element-by-element basis. 相似文献
42.
构建水平潜流人工湿地装置,通过NaCl示踪脉冲实验,得到不同水力负荷条件下的水力停留时间分布密度曲线,根据不同停留时间的关系计算相对水力效率,并利用染料,进行不同水力负荷下的可视化示踪实验,通过MATLAB处理得到高对比度的流态图像。观察"死区"分布,计算"死区"相对面积用以表征其水力效率。结果表明,湿地装置进水水力负荷较高或较低时,水力效率均较低,且水力负荷较大时更明显;水力分布散度(σ2θ)的大小会对水平潜流人工湿地水力效率造成较大影响;在不同水力负荷下,采用水力学效能(λ)所得到的排序结果相比短路值(s)和有效体积比(e)更能代表实际水平潜流人工湿地的水力效率。 相似文献
43.
利用Fe(Ⅱ)EDTA络合吸收-铁粉间歇还原再生脱除NO并回收氨资源的方法,实验研究了铁粉还原再生Fe(Ⅱ)(NO)EDTA的过程及其影响因素。结果表明,以0.015 mol/L的Fe(Ⅱ)EDTA做吸收剂,在起始p H 5.5、温度323K条件下吸收400×10-6~500×10-6的NO,脱除率95%以上;铁粉还原再生Fe(Ⅱ)(NO)EDTA过程可用缩芯模型阐释;铁粉添加量与搅拌强度直接决定了铁粉质点数量,是影响反应的重要因素;实验中Fe(Ⅱ)(NO)EDTA络合液150 m L,氧气含量为5%时,搅拌速度900 r/min、粒径为0.12 mm的铁粉浓度5.3 g/L、温度353 K、p H=6为最适宜再生条件。 相似文献
44.
将活性污泥培养及驯化后接种于生物滴滤塔中,挂膜启动后处理模拟氯苯废气(简称氯苯废气),考察了生物滴滤塔在挂膜启动阶段及稳定运行阶段的性能。实验结果表明:接种41 d后生物滴滤塔成功挂膜,此时氯苯去除率稳定在90%以上;生物滴滤塔稳定运行阶段,随着进气中氯苯质量浓度由303.82 mg/m3逐渐增至1 489.05 mg/m3,氯苯去除率从85.1%降至70.1%。处理氯苯废气适宜的工艺条件为:空塔停留时间超过45 s,喷淋液流量31.8 mL/min,氯苯负荷23.97~128.01 g/(m3·h)。生物滴滤塔对喷淋液的酸性环境有较好的适应性,喷淋液pH的变化对氯苯去除率无显著影响。 相似文献
45.
为有效处理含异噁草酮除草剂废水,以Sb掺杂Ti/SnO2电极为阳极,不锈钢板为阴极,采用电催化氧化技术对异噁草酮废水进行降解,研究了不同影响因素对异噁草酮去除率的影响,并分析了异噁草酮的降解效果。结果表明,当异噁草酮初始浓度为100mg/L、电流密度为20mA/cm2、电解质投加量为0.10mol/L,反应120min后,异噁草酮去除率达到94%,此时TOC去除率为57.9%,能耗为25kWh/m2,且废水的可生化性能显著提高。 相似文献
46.
Temperature-dependent sorption of polycyclic aromatic hydrocarbons on natural and treated sediments 总被引:1,自引:0,他引:1
In aqueous environment temperature is considered to play a significant role in the sorption process of polycyclic aromatic hydrocarbons (PAHs) and its influence on the sorption equilibrium is indicative of sorption energies and mechanisms. In this study, sorptions of five PAHs on three heterogeneous sorbents including one river sediment (YHR), one estuary sediment (YRD) and one treated sediment with organic matter removed (IM) were carried out at a range of temperature from 5 °C to 35 °C. Stronger sorptions were observed at lower temperatures, with the equilibrium sorption coefficient Kd increasing 2-5 times as the temperature decreases 30 °C. The increase of Kd value was attributed primarily to the change of PAH water solubility, which predicted 40-75% of the increase of Kd in the sorption process. To provide insight into the sorption mechanism, enthalpy change (ΔHS) for the sorption process was calculated and the values were observed to be negative for all of the interactions, suggesting that the exothermal sorption of PAHs inversely dependents on temperature. Based on the values of ΔHS, van der Waals forces were inferred as the main sorption mechanism for the PAHs, especially on the YHR sediment which contained more organic matter. For sorption of larger size PAHs on the sorbents with low organic matter, specific interactions were deduced to contribute to the overall sorption. 相似文献
47.
Field open top chambers (OTCs) and soil mercury (Hg) enriched experiments were employed to study the influence of Hg concentrations in air and soil on the Hg accumulation in the organs of maize (Zea mays L.) and wheat (Triticum aestivum L.). Results showed that Hg concentrations in foliages were correlated significantly (p < 0.05) with air Hg concentrations but insignificantly correlated with soil Hg concentrations, indicating that Hg in crop foliages was mainly from air. Hg concentrations in roots were generally correlated with soil Hg concentrations (p < 0.05) but insignificantly correlated with air Hg concentrations, indicating that Hg in crop roots was mainly from soil. No significant correlations were found between Hg concentrations in stems and those in air and soil. However, Hg concentrations in upper stems were usually higher than those in bottom stems, implying air Hg might have stronger influence than soil Hg on stem Hg accumulation. 相似文献
48.
49.
Dai Shijin Zheng Yilin Zhao Youcai Li Qiang Niu Dongjie 《Environmental science and pollution research international》2019,26(10):9480-9489
Environmental Science and Pollution Research - Chlorine-containing organic waste (COWs) is a big threat for the waste incineration because of the dioxin generation and equipment corrosion.... 相似文献
50.